Cedar Rock State Park

Cedar Rock State Park is a 426-acre (172 ha) state park in Buchanan County near Quasqueton, Iowa, United States. The park's primary structure is the Lowell Walter House, also known as Cedar Rock, designed by Frank Lloyd Wright in the Usonian style for the local businessman Lowell E. Walter and his wife Agnes. The Walter House, a one-story residence, is constructed on a bluff above a bend of the Wapsipinicon River. The park also includes a gate, fireplace, and boathouse designed by Wright, as well as other visitor amenities such as a visitor center. The house is on the National Register of Historic Places.

Lowell Walter had become a successful businessman by 1942, when he contacted Wright to design a house at the site. Wright completed the design in 1945, but due to material shortages, construction did not begin until 1948. The house was completed in 1950 and, after hosting two public open houses, functioned as the Walters' summer home for three decades. After Walter died in 1981, he bequeathed the property to the state government, which opened it to the public in 1982. The visitor center was completed in 1989. The house has undergone several renovations after the state's takeover.